Circuit interrupter



Aug. 31 '1926.

C. AALBORG CIRCUIT INTERRUPTER Filed Dec. 1919 2 Sheets-Sheet 1 INVENTOR Chr/lrfi'anfla/bory.

464/4 TTORNEY M II . WITNESSES. a. W

Aug. 31 1926.

WITNESSES 1,597,750 QAALBORG Y C IRCUIT INTERRUPTER F'iled'Dac. 22 1919 2 Sheets-Sheet 2 (646417 ATTORNEY Patented Aug. 31, 1926.

UNITED STATES PATENT OFFICE.

.CHRISTIAN AALBORG, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

CIRCUIT INTERRUPTER.

Application filed December 22, 1919. Serial No. 346,779.

My invention relates to circuit interrupters and particularly to quick-acting circuit interrupters.

One object of my invention is to provide a circuit interrupter that shall open quickly.

Another object of my invention is to provide a circuit interrupter that shall move a relatively small distance when opening and thus preclude excessive stresses, such as might occur by reason of the momentum of moving parts having large inertia.

A further object of my invention is to provide a circuit interrupter that shall be simple, compact and rugged in construction and quick and positive in operation.

In practicing my invention, I provide a circuit interrupter havinig an operating handle, laminated copper brushes that constitute the stationary contact members, a solid copper plate, reinforced by steelplates, that constitutes the movable contact member, auxiliary arcing contact members, an arc chute and a magnetic blowout device associated therewith, an electromagnet that is adapted to hold the circuit interrupter closed, a plurality of sprinlgs adapted to be so compressed by the closure of the circuitinterrupter as to accelerate the opening thereof when the circuit interrupter is released.

An auxiliary winding is connected across the terminals of a reactor in the circuit that is to be protected and is so disposed, with respect to the air gap of the electromagnet, as to shift the flux that normally traverses the armature, to an auxiliary path to thus render the armature non-responsive to the electromagnet. The compressive force of the springs, being transmitted directly to the movable member of the interrupter, immediately actuates the same when the auxiliary winding is energized.

Figure 1 in the accompanying drawings is a side view, partially in elevation and partially in section, of a circuit interrupter embodying my invention, Fig. 2 is a plan view of the electromagnet shown in Fi 1;Fig. 3 is a diagram of the connections 0 the electromagnet to the circuit. Fig. 4 isa plan view of the electromagnet and its supporting member, and Fig.5 is a plan view of the arc chutes and of the magnetic blow-out device shown in Fig. 1.

A circuit interrupter that is mount ed on panel 2 comprises an operating handle 3, stationary contact members 4 and 5, a movable contact member 6, auxiliary arcing contact members 7 and 8, an arc chute 9, a magnetic blowout'device 10 and an electromagnet 11. The operating handle 3 is pivotally mounted on a shaft 12 that is mounted in a supporting casting 13. The movable contact member 6 is pivotally mounted on a shaft 14: that is supported by the casting 13. The operating handle 3 is adapted to close the circuit interrupter 1, through a togglelink mechanism 15, by the pressure of a cam member 16 against the movable contact member. 6. A spring 17 is so disposed between the shaft 12 and the handle 3 as to return the operating handle 3 to its initial position after the circuit interrupter 1 has been closed, in order that the link mechanism may not retard the quick opening movement of the movable member 6. A bumper 18 is provided to serve as a stop member for the movable contact member 6 when the circuit interrupter 1 opens. The stationary contact members 4 and 5 comprise laminated copper brushes that are so disposed, when the circuit interrupter opens, that the movable contact member 6 becomes disengaged from the stationary contact member 5 before it passes out of engagement with the stationary contact member 4:. The auxiliary arcing contact member 8 is pivoted at 8 to the bridging member 6 and is yieldingly held in advanced position by a spring 8 so that the auxiliary arcing contact members 7 and 8, however, remain in engagement until the movable contact member 6 and the stationary member 5 become disengaged. The are that is drawn when the arcing contact members 7 and 8 become disengaged is enclosed by an arc chute 9 that is disposed vertically above the arcing members 7 and 8 and is provided with the usual insulating walls 9. The magnetic blowout device 10 comprises a magnetizable core 19 and a winding 20.

Theinagnetic field produced by the magnetizable core 19 and that produced by the current traversing the arc so react as to force the arc upward and thus cause it to break. The winding 20 is electrically and mechanically connected to the stationary contact member 5 through a casting 20 and serves as a terminal stud therefor.

' The electromagnet "11' comprises a mag.

netizable core member 21, an armature 22, a potential winding 23 for energizing the core 21 and an auxiliary winding 24 that is disposed around arms 25 for so shifting the flux that normally traverses the armature 22, through the path comprising the arms 25, as to render the armature 22 nonresponsive to the core member 21. The auxiliary winding 2% is connected across the terminals of a reactor 26 that is connected in series with the circuit 27 which to be protected. A rod 28 extends through the panel 2 and connects the armature 22 to the movable contact member 6. A spring 29 is slidably mounted on the rod 28, between the front taco of the panel 2 and the movable contact member (3. A. casting 30, on the rear of the panel 2, supports the elec tromagnet 11 which is secured to the casting by bolts l1 (Fig. at).

hen the circuit interrupter 1 is closed by the operating handle 3. the electromagnet 11 holds the armature 22 and maintains the circuit interrupter 1 closed against the force of the springs 29. The auxiliary winding 2% of the elect-romagnet 11 is energized by the increased voltage that is produced across the terminals of the reactor 26 when the current traversing the circuit interrupter 1 is increased quickly. The flux that normally traverses the armature 22 is shifted to the auxiliary path, through the arms 25, by the auxiliary winding 24-, and the armature 22, being no longer responsive to the electromagnet 11, is disengaged from the core 21, and the circuit interrupter is opened by the direct force of the con pressed springs 29. The bumper 1S limits the movement of the movable member 6, and the use of the auxiliary arcing contact members '7 and 8 obviates the necessity for a large separating movement. The movable contact member 6 is made of a solid copper plate 31 s cured to, and reinforced by, a block Although I have shown only one form of circuit interrupter embodying my invention, I do not wish to limit it to the structure shown, as various modifications may be made therein without departing "from the spirit and scope of the invention as set forth in the appended claims.

I claim as my invention:

1. In a circuit interrupter, the combination with an operating handle, of a movable bridging member adapted to be actuated thereby, a plurality of resiliently mounted contact members adapted to be bridged by the bridging member. an electromagnet, an armature associated therewith for holding the circuitinterrupter in its closed position, a rod oining the armature and the movable bridging member, a winding for rendering the armature non-responsive to theelectromagnet, and a/spring mounted on the rod for quickly opening the circuit interrupter when the armature is released by the elec' tro-magnet.

2. In a circuit interrupter, the combination with an operating handle, of a movable bridging member adapted to be actuated thereby, a plurality o't resiliently mounted contact members adapted to be bridged by the bridging member, an elect1.'o1na rnet an armature associated therewith, a winding t r energizing the electromagnet, a second winding tor rendering the armature nonresponsive to the electromagnet, a rod joining the armature and the movable bridging member. and a spring "for quickly opening the circuit interrupter when the armature is released by the electromagnets.

3. In a circuit interrupter, the combination with an operating handle, of a panel, a plurality o't stationary and movable conta t mem 'iers supported at one side of the panel, a holding magnet disposed at the other side of the panel, a winding tor enermg the magnet. an armature adapted to be held by the magnet, a connection between the armature and the movable contact member whereby the circuit interrupter is held closed, a winding for rendering the armature HOD-TOSPOHSlVO to the clectromagnet, and means for opening the circuit interrupter upon the release of the armature.

4. In a circuit interrupter mounted on a panel, the combination with an operating handle on the trout ot the panel for closing the circuitinteri 'u 1 ter, of an eleetroi'nagnet on the rear of the panel for holding the circuit interrupter closed, a winding for energizing the electromagnet, a plurality of stationary and movable contact members. a rod extending from the movable contact member through the panel to an armature ot the electromagnet and adapted to hold the circuit interrupter closed while the armature is re ponsive tothe electromagnet, a winding re ponsive to a quick change of current through the circuit interrupter for rendering the armature non-responsive to the magnet, a spring for quickly opening the circuit interrupter upon the rendering of the armature non-responsive to the electromagnet, and a stationary and a movable arcing contact member.

A circuit interrupter comprising a panel, a pair of stationary contact members, a bridging member for the cont-act members, means for moving the bridging men'iber to closed position, a holding magnet disposed at the side of the panel, opposite to the side occupied by the other p0r tions of the apparatus, an armature co-operating with the magnet, a connecting member extending through the panel and having its ends joined to the bridging member and the armature, and a yielding member interposed between thebridging memher and the panel in osition to be compressed when the bridging member is moved to closed position, the said yielding member acting to open the interrupter when the armature is released by the mag net.

6. A circuit interrupter comprising a anel, a pair of stationary contact memers, a bridging member for the contact members, an operating lever for moving the bridging member to closed position, means for returning the said lever to retracted position when the bridging member has been closed, a holding magnet disposed at the side of the panel opposite to the side occupied by the other portions of the apparatus, an armature co-operating with the magnet, a connecting member extending through the anel and having its ends joined to the ridging member and the armature, and a yielding member interposed between the bridging member and "the panel in position to be compressed when the bridging member is moved to closed position, the said yielding member acting to open the interrupter when the armature is released by the magnet.

7 A circuit interrupter comprising a panel, a pair of stationary contact members, a bridging member for the contact members, means for moving the bridging member to closed position, a holding magnet disposed at the side of the panel opposite to the side occupied by the other portions ofthe apparatus, an armature cooperating with the magnet, a connecting member extending through the panel and having its ends joined to the bridging memher and the armature, and a yielding member connected to the bridging member and a fixed support and arranged to be stressed when the bridging member is moved to closed position, the said yielding member acting to open the interrupter when the armature is released by the magnet.

In testimony whereof, I have hereunto subscribed my name this 17th day of December, 1919.

CHRISTIAN AALBORG. 

